Sealing tapes of soft and flexible foam material are used in the construction industry to provide a seal against drafts and driving rain. For household use by the end user, there are generally known foam tapes with a thickness of usually a few millimeters, which are provided on one side with a self-adhesive layer covered by a cover film and are wound up uncompressed into rolls. They are used between window or door panels and the window or door frames to seal leaky windows and doors. For this purpose, they are adhered to suitable points on the panel or frame.
In the professional building construction industry, sealing tapes, usually impregnated, of soft and flexible foam material are used between window and door frames and the masonry. These types of sealing tapes can be up to a few centimeters thick and are usually provided on one side with a self-adhesive layer, by means of which they can be adhered to the frame profile elements of windows and doors. So that a component which has been provided with the sealing tape can be installed more easily at the construction site, sealing tapes of this type are frequently impregnated with a material which delays the recovery of the foam material from its compressed state, i.e., the state in which it has been delivered on a roll, back to the expanded state.
To prevent the diffusion of vapor, it is necessary to use sealing tapes of the previously mentioned type which have been provided with a vapor barrier. A sealing tape of open-pored material which has been rolled up into a disk and which is used to seal joints or gaps against drafts and driving rain is known from DE 196 41 415 C2, in which at least one barrier layer is arranged inside the sealing tape in such a configuration that it and the adjacent open-pored areas form a row in the axial direction. The barrier layer therefore extends in the radial direction of the sealing tape roll.
To produce a sealing tape of the last-mentioned type, large sheets of barrier layer material are formed into laminated blocks by laminating and/or adhering layers of them to panels or to web material of open-pored raw foam. The laminated blocks are then cut at right angles to the large sheets of barrier layer lamination material and/or to the adhesive to obtain plates with barrier layers. The blocks are cut in such a way that, after the cutting operation, the barrier layers are parallel to one edge of the panel and extend perpendicularly through the panel. A panel of this type is then compressed and wound up into a roll in such a way that the barrier layers and the open-pored material form a row in the axial direction on the circumference of the roll. Finally, the roll is cut into disks between the individual barrier layers. This process is relatively complicated and demands a high degree of dimensional accuracy from the foam material during processing, because otherwise there is the danger of damage to the barrier layers when the roll is cut into disks.
A method by means of which plastic bodies of open-pored foam can be provided on their outside surfaces with a polyurethane coating by spraying is known from DE 24 57 322 A1. This method, however, demands special measures for the preparation of the foam. It is therefore not suitable for application to compressed foam bodies which are intended to expand again when put into use, because the coating applied in the compressed state would interfere with the expansion or possibly make any such expansion impossible. If only a thin coating were to be applied, i.e., thin enough to allow the foam to expand, there would be the danger that the coating would crack. For technical reasons, the application of the coating by spraying in the expanded state is uneconomical in the case of sealing tapes.
WO 98/45565 shows sealing tape with a removable film coating, which covers three sides of the sealing tape in the compressed state.